it has been discussed a few times :) https://issues.apache.org/jira/browse/CASSANDRA-494
A ----------------- Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 25/02/2012, at 8:06 AM, Praveen Baratam wrote: > Thank you Aaron for the clarification. > > May be this could be a feature that Cassandra team should consider > implementing. Instead of two network round trips the logic could be > consolidated on the server side if read before range delete is unavoidable. > > On Fri, Feb 24, 2012 at 12:46 AM, aaron morton <[email protected]> > wrote: > Unfortunately you can use column ranges for delete operations. > > So while what you want to do is something like... > > Delete 'Jack:*:*'...'Jack:*:*' from Test where KEY = "friends"; > > You cannot do it. > > You need to read and then delete by name. > > Cheers > > ----------------- > Aaron Morton > Freelance Developer > @aaronmorton > http://www.thelastpickle.com > > On 23/02/2012, at 8:08 PM, Praveen Baratam wrote: > >> More precisely, >> >> Lets say we have a CF with the following spec. >> >> create column family Test >> with comparator = 'CompositeType(UTF8Type,UTF8Type,UTF8Type)' >> and key_validation_class = 'UTF8Type' >> and default_validation_class = 'UTF8Type'; >> >> And I have columns such as: >> >> Jack:Name:First - Jackson >> Jack:Name:Last - Samuel >> Jack:Age - 50 >> >> Now To delete all columns related to Jack, I need to use as far as I can >> comprehend >> >> Delete 'Jack:Name:First', 'Jack:Name:Last', 'Jack:Age' from Test where KEY = >> "friends"; >> >> The problem is we do not usually know what meta-data is associated with a >> user as it may include Timestamp based columns. >> >> such as: Jack:1234567890:Location - Chicago >> >> Can something like - >> >> Delete 'Jack' from Test where KEY = "friends"; >> >> be done using the First N components of the CompositeType? >> >> Or should we read first and then delete? >> >> Thank You. >> >> On Thu, Feb 23, 2012 at 4:47 AM, Praveen Baratam <[email protected]> >> wrote: >> I am using CompositeType columns and its very convenient to query for a >> range of columns using the First N components but how do I delete a range of >> columns using the First N components of the CompositeType column. >> >> In order to specify the exact column names to delete, I would have to read >> first and then delete. >> >> Is there a better way? >> > >
